Think about this for a minute. If you have both sprockets fixed, what will happen to the chain when the alignment changes? When your rear axle gets bumped while racing, no matter how many lock collars you have on the axle, it will move in or out depending on which side got hit. Because of this jarring, the possibility of throwing the chain is greatly increased. Once the sprockets are misaligned, there is a tremendous side-load, which will cause the chain to become extremely hot from the friction. This causes the chain to stretch, pop the master link (which we don't ever recommend using) or the chain breaks. When you spin around and do a 180 (drive in reverse), many times the axle flexes so much that it will toss the chain. Floating the clutch will keep you in the race - it compensates for the flex and change in alignment.

At a race, I was shown a Raptor engine whose crankshaft length only measured 2.240", not the standard 2.300". This will cause problems when mounting any clutch because the shaft will not protrude through the clutch. As you tighten down on the crankshaft bolt, you put pressure on the snap ring area of the clutch which will make it flare out. This in turn will make it difficult to take the drum off the clutch unless you file the snap ring area down (you should never have to do this). This is a common problem with a Ratech clutch because their clutch extends past the end of the crankshaft. Place a spacer washer in the inside of the sleeve (journal) to prevent ruining the clutch.

How much float can you give the clutch? We like to use two washers. We use a lathe to turn down the washer to .748 diameter. These washers are .050 to .075 thick. You can go to the hardware store and buy a standard flat washer that has a 5/16 hole and is 11/16 in diameter. They are then placed under our flat washer on the end of the crankshaft. What we are trying to do is extend the crankshaft's overall length. It does not make any difference if you mount the clutch onboard or outboard when it comes to floating the clutch. When using a Ratech clutch make sure the key does not bind in the keyway because you want the clutch to be able to go back and forth on the shaft easily. Never force any clutch on the crankshaft. Take the time to remove burrs, file the key if needed. The DRAGGIN SKIN has a built-in key in the hub that is .186 wide so it easily fits the .187 keyway.

First, put your clutch on the crankshaft (inboard or outboard), then place the turn downed spacer washer(s) on the 5/16 bolt (see drawing). Just before you torque down the bolt, make sure the clutch slides freely on the crankshaft and there is no bind on the washers you added to the inside of the sleeve or hub. Position the clutch halfway between the crankshaft step and your 1 1/8" flat washer.

In order to benefit from the float, you must position the clutch so that it can travel in either direction - towards the engine or away from it. Centering it on the crankshaft is very important. Last thing to do is to align your rear sprocket to the clutch sprocket while it is centered between the two stops. If you use one washer that is .070 thick and you center the clutch, the amount of float is only .035 thousands which is about a 1/32". Believe me, the clutch is not going back and forth on the shaft unless it is needed. But, when it is needed, now the clutch has the opportunity to correct any misalignment that occurs while you are on the track. The important thing is finishing the race, winning is the challenge.

The flat washer that you hold the clutch on with should be 1 1/8" in diameter and the length of the 5/16" bolt should be 3/4" long. Don't use longer bolts because you don't need them. One thing I noticed in the pits is that drivers torque the "heck" out of the bolt that holds the clutch on. It just needs to be snug, a quick tap once it is seated is sufficient. The clutch has no place to go because the chain of the rear sprocket holds it in place.

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